Emil volkers



E. VOLKERS.

ELECTRIC MOTOR FOR SMALL OUTPUTS. APPLICATION FILED MAR.I2.19H.

7 1,322,659. Patented Nov. 25, 1919.

Emil W11 61:

EMIL VOLKERS, 0F

BERLIN, GERMANY.

ELECTRIC MOTOR FOR SMALL OUTPUTS.

Specification of Letters Patent.

Patented Nov. 25, 1919.

Application filed March 12, 1917. Serial No. 154,312.

To all whom it may concern:

Be it known that I, EMIL VoLKnns, a subject-of the German Emperor, residing at Berlin, 83/36 Liitzowstrasse, Germany, have invented new and useful Improvements in Electric Motors for Small Output-s; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and usethe Same.

This invention relates to electromotors and more particularly to such motors for small outputs as are used for driving clocks, toys, small ventilators or fans, etc.

The new design is an improvement of the electric motor in its first stages of development. The rotary motion of a wound "armature that is usual in motors of the present day has been replaced by an oscillating movement of a bare armature.

This step, although retrograde from a general engineering point of view, was taken in order to secure very considerable advantages in the cheapness of design.

The new motor is exceedingly simple. It has only a round coil of wire and a current interrupter. However small the motor may be, it may be connected without any preto cautions without a rheostat to electric light mains. It operates equally well w1th continuous or alternating current. The mode of operation will be understood from the drawing which shows a diagrammatic representation of the motor.

Loosely mounted on the driving shaft 1 but coupled to this shaft by a spring 2 is small fly-wheel 3 that receives short propelling strokes from a pawl 4 that is actuated by the draft rod 5 and the armature 6 of the electromagnet 7. At each downward stroke the end of the pawl comes into firm frictional engagement with the circumference of the wheel 3 and turns the wheel in the direction indicated by the arrow, but during its upward motions it simply glides over the periphery of the wheel.

The propelling strokes are of such force that the motion imparted to the flywheel 3 continues after the armature 6 strikes its pole 8 until the momentum of the wheel is stored up in the spring. After executing its active stroke the armature is restored by a spring (indicated in the drawing at 16) to the position in which it is prepared for the next propelling stroke, which occurs before the tension of the spring 2 has time to swing the fly-wheel 3 in the direction opposite to that indicated by the arrow.

The opening and closing of the circuit in which the current through the electromagnet T flows is executed by the two contacts 9 and 10.

The contact 9 is mounted on the two-arm lever 11 that rocks on a shaft 15 driven by the motor in the direction indicated by the arrowf with the aid of any suitable means, say, by pulleys and a belt, as indicated at 17. The lever 11 is not fast upon the shaft 15; it is coupled to it by a frictional coupling 18 by which its rotation with the shaft is secured, but which allows the lever to be knocked backward when, on the engagement of the contacts 9 and 10, the armature 6 and its brass pin 12 imparts an upward move ment to the lever 13 and causes the rod 14 to bump against the lever 11. The next propolling stroke is executed by the electromagnet as soon as th lever 11 again causes the contacts 9 and 10 to close. The electric circuit may be arranged as indicated in the drawing.

The motor may be started by manually swinging the lever 11 to bring together the contacts 10, 9, thus completing the circuit and energizing the coil 7. The armature 6. being attracted, will perform two functionsi first, it will drive the fly-wheel, through the pawl 4:; second, it will, through the parts 12, 13, and 14, knock the lever 11 back so as to separate the contacts 9, 10 and break the circuit. The coil 7 now being deenergized, the armature moves away from it (urged by the spring 16), the pawl f slipping over the fly-wheel 3 which still rotates in the same direction, carried on by its momentum; at the same time, the parts 12, 13, 14 return to their former position. As the fiy-wheel continues to rotate (under the influence of its momentum), and continues to drive the shaft 15, the latter carries the lever 11 in the direction indicated by the arrow and thus again establishes contact at 9, 10, whereupon the cycle is repeated. The knocking backward of the lever 11 breaks the circuit quite suddenly. It will be understood that the lever 11 rocks, but does not rotate. The spring 2 provides an elastic coupling, as it were, between the fiy-wheel 3 and the shaft 1 and the parts connected with said shaft.

A remarkable advantage of the described contact. device is that the contacts are firm-1y pressed against each other and are widely separated at precisely the correct moment at a great speed.

I claim:

1. An electric motor comprising a coil, an armature actuated by the said coil, a rotary member propelled by the armature, an element driven by the rotary member, a con tact member, a contact holder attached to the element by a releasable attaching means and moved toward contact member, and means actuated by the armature for displacing the said contact holder upon the said element when the contact holder touches the contact member.

2. An electric motor comprising an electromagnet with an armature and a pawl, a shaft rotated by the pawl, a circuit for energizing the electromagnet, and a contact device for closing and opening the circuit, said contact device consisting of a primary contact member moved byfriction with the said shaft and a secondary contact member actuated by the said armature, the primary con tact device being moved by the rotation of the shaft toward the secondary contact device until the circuit is closed, when the armature is attracted and causes the secondary contact member to deliver a blow against the primary contact member causing this member to shift upon the shaft in a direction away from the secondary contact member, whereby the circuit is broken and thearmature released by its electromagnet until the primary contact member'again reaches the secondary contact member.

3. An electric motor comprising an electromagnet, a rotor driven by the electromagnet, a circuit including the electromagnet and a primary and secondary contact mem- 4o ber, means by which the rotor drives the primary contact member toward the secondary contact member, means by which the electromagnet knocks the primary member all! from the secondary member when both many 48 bers come together, and means by which the motion of the primary member toward the secondary member is always renewed after the said action of the armature.

4 An electric motor comprising an clas to tromagnetic coil, an armature adapted to be attracted by said coil, a rotary member, means for rotating said member by the tociprocating movement of the armature, a rotary element driven by said rotary nm- 86 ber,..amircuit-controlling member connected loosely with said rotary element to be n0rmally driven thereby in one direction, capable of swinging back in the opposite rection, contact mechanism adapted to he given the contact-making position by movement of said circuit-controlling menl her in one direction, and means, operated by the movement given to the armature by the, attraction of the coil. for swinging saidoi 3 Q a wit-controlling member in the oppqsififi a i m r44 U rection, to the contact-breaking position. f T

In testimony whereof I have signed specification in the presence of two subscrib ing Witnesses. g EMIL VOLKERS. i y 1 Witnesses:

HENRY HASPER, ALLEN F. JENNINGS. 

